25% means 0.25 (It also means 1/4.) 50% means 0.5 (It also means 1/2.)
0.25 of 30.44 = 7.61
0.5 of 13.50 = 6.75
From 7.61, subtract 6.75.
OK. I did it. The question just says "do it". It doesn't ask us what the result is.
If anybody asks you, you can do the subtraction, or just tell them it's 0.86 . (Is that 86 pence?)
25% ⋅ \£ 30.44 − 50% ⋅ \£ 13.50 = 0.25 ⋅ \£ 30.44 − 0.5 ⋅ \£ 13.5 = = \£ 7.61 − \£ 6.75 = \£ 0.86
The calculation shows that 25% of £30.44 is £7.61, and 50% of £13.50 is £6.75. Subtracting these two results gives £0.86. Therefore, the final answer is £0.86.
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